In previous work, we have related the mechanics of muscle contraction to the biochemical kinetics, the latter being expressed in terms of "given" rate constants. We have begun, during the current year, an attempt to go one step more deeply into the kinetics by studying the molecular theory of the rate constants themselves. One part of this work deserves special comment; it extends the range of validity of Eyring's widely used rate theory (for gas reaction) to include solution reactions and diffusion effects. We have also investigated the connection between free energy levels of a cycling macromolecule (e.g., an enzyme) at steady-state and the kinetics of the cycle. The entire subject of steady-state kinetics and thermodynamics, and its relation to free energy trasduction in biology, is being treated in a monograph that will be completed during the current year.